What is the latest teeth whitening method other than bleaching? is that safe?

Well...: There are some whitening techniques that use a light or a laser to help 'activate' the bleaching gel. If it's performed in a dentist's office, it's most likely safe. Having said this, i'm personally not a big fan of these newer techniques. I've tried them and haven't found them to work very well. Your best result will be with bleaching trays made by your dentist & rx-strength bleaching gel.

Laser: Some dentist are using laser bleaching treatment and it is safe.

Restorations: The only way to whiten w/o bleaching is to place restorations (porcelain/composite laminates or crowns) on the teeth that show. This usually involves removing some healthy tooth structure, so if the only issue is the color of the teeth, bleaching is the best alternative.

Prepless veneers: Rather than use whitening gels, ask your dentist for prep-less or feldspathic or leucite reinforced thin veneers, or minimally invasive veneers, these are great options to consider, and they don't discolor. If you have too much crowding or bad bite, malocclusion, this may not work for you unless you have braces first.

Bleaching: Bleaching is the only method to change the shade of teeth, which has been done for decades and is safe when not overdone. The term whitening is an fda term specifically to remove surface stains from teeth, not to change tooth color.